A method of estimating the critical buckling load for structural members
A 1939 NACA technical note on estimating critical buckling loads for structural members, issued by the National Advisory Committee for Aeronautics as a research report for engineers and aeronautical designers. The pictures are plain engineering line graphs with gridded axes, straight data lines, and marked data points, each labelled with load values in pounds and figure numbers. A designer might take from them the restrained look of technical charts, with simple labelled axes, sparse black linework, and clean data markers.
